Semiconductor wafer probers are a type of automatic test equipment (ATE) employed to test individual die within a semiconductor wafer after fabrication (e.g., prior to packaging of the die). Wafer testing typically employs a prober that includes a wafer chuck configured to hold the semiconductor wafer and a tester head that supports a load board printed circuit board (PCB), which provides an interface between the semiconductor wafer and the test system. The load board PCB is interconnected with a probe card PCB having a probe head that includes a set of probe pins (e.g., microscopic contacts) that engage pads (and/or solder bumps) disposed on the individual dice within the wafer. A spring pin tower provides connectivity between the load board PCB and the probe card PCB, which is mounted to the prober, when the test head is interfaced with the prober. During testing, the probe card PCB and probe head are held in place, while the semiconductor wafer, vacuum-mounted on the wafer chuck, is moved into electrical contact with the probe pins of the probe head.
To test a die (or set of dice), an operator loads a test program that furnishes a predefined set of input values (e.g., power source, clock input, stimulus values, etc.) to the test system. An operator also loads a wafer map file to the prober that furnishes a predefined pattern that the wafer prober chuck will use to manipulate wafer movement and associated interface with the load board PCB. The load board PCB, via the spring pin tower, probe card PCB, and probe head, furnishes these input values to the die (or set of dice), and receives the output produced by the integrated circuits disposed on the die. When a die (or set of dice) have been tested, the prober moves the semiconductor wafer to the next die (or set of dice) in the wafer for testing of that die (or set of dice).